Reducex

reducex is a lightweight JavaScript library that helps you transform and reduce flat arrays into complex structures while grouping and keeping unique values. With a simple and flexible API, you can easily define the structure of your desired output and reduce any flat array into nested objects or arrays.

Installation

To use this library, you need to install it in your project. You can do this using npm:

npm install reducex

Or using yarn

yarn add reducex

Usage

Import the transform function from the reducex package:

import { transform } from 'reducex';

Basic Example

Suppose you have the following flat array of orders with products:

const orders = [
  {
    orderId: 1,
    orderName: '10001',
    productId: 1,
    productName: 'md size',
  },
  {
    orderId: 1,
    orderName: '10001',
    productId: 2,
    productName: 'sm size',
  },
];

You want to transform this array into a nested structure that groups products by their orderId. First, define the desired structure using the model function:

const model = (order, key) => ({
  id: key(order.orderId),
  name: order.orderName,
  products: (product, key) => ({
    id: key(product.productId),
    name: product.productName,
  }),
});

Next, use the transform function with the orders array and the model function as arguments:

const result = transform(orders, model);

The result will be:

[
  {
    id: 1,
    name: '10001',
    products: [
      {
        id: 1,
        name: 'md size',
      },
      {
        id: 2,
        name: 'sm size',
      },
    ],
  },
];

API

transform(inputArray, modelFunction)

• inputArray (Array): The input flat array you want to transform.
• modelFunction (Function): The function that defines the desired structure.

Returns a new array with the transformed structure.

Model Function

The model function is used to define the desired structure for the output array. It should return an object with the desired properties and nested structures.

The function receives two parameters:

• The first parameter is an element from the input array.
• The second parameter is the key function used to generate unique keys for the output structure.

Nested structures should be defined as functions, which also receive the key function as the second parameter.

License

MIT